Quad S-2 loudspeaker

One of the better things about bookshelf loudspeakers is that they're innately portable. Though not generally considered the sort of music-reproduction machines you'd bring to a party, a 12-step group, or a Burning Man rave (though you certainly could), high-quality bookshelf speakers are overlooked tools in the eternal work-in-progress of introducing lovers, friends, and family to our beloved lifestyle. So during the first week or three of breaking in the Quad S-2 bookshelf speakers, I thought, Why keep these to myself? It's strict Stereophile policy that all gear be evaluated in the context of the reviewer's reference hi-fi rig(s), but there's no law against sharing the joy.

In their single shipping box, the S-2s together weigh about 28 lbs—it was easy for me to tote them all over New York City and environs and temporarily install them in the meager system of a Chelsea record store, in my girlfriend's entry-level rig in Forest Hills, Queens, and in my sister's none-too-shabby hi-fi (Cambridge Audio Topaz AM10 integrated amp, Pro-Ject Debut III record player) in Spring Lake, New Jersey. Everyone welcomed the sophisticated-looking, small-footprint S-2s—particularly my British brother-in-law, who fondly recalled his dad's classic Quad gear from the 1960s.

At the end of this peripatetic break-in period, I safely re-ensconced the Quad S-2s in my Greenwich Village apartment, where I listened to them in my smaller rig of Music Hall MMF 7.3 turntable and Heed amplification, and my majordomo system comprising a Kuzma Stabi and Stogi turntable and tonearm, and a Shindo Laboratory Allegro preamp and Haut-Brion power amp.

I'd reviewed high-end audio gear for various websites for 20 years before John Atkinson graciously took on this former Southern boy in 2015. That's when my real work began. But we all have history, right? And perhaps no audio history is as glorious as that of the British audio manufacturer Quad, now owned by the IAG Group, which manufactures Quad products in Shenzhen, China.

Innovator and audio designer Peter J. Walker founded S.P. Fidelity Sound Systems in 1936, and later that year changed its name to Acoustical Manufacturing Co. Ltd. After a decade of making public-address systems, their first commercial home-audio product came in 1948: the QA/12P integrated amplifier. (Quad was originally an acronym for Quality Unit Amplifier Domestic.) In 1949, the QA/12P was joined by another Walker design, the Corner Ribbon (CR) loudspeaker: the very first speaker to use the hybrid technology of a ribbon loaded by a horn.

The Quad QCII preamplifier and II power amplifier were introduced in 1953, followed four years later by the commercially successful Quad Electrostatic Loudspeaker or ESL, referred to unofficially as the ESL-57 and nicknamed "Walker's Wonder." The ESL remained in production for 28 years, and was eventually succeeded by the equally lauded ESL-63, which wowed the faithful until 1999. The ESL design is venerated for its low distortion, palpable midrange, brilliant transparency, transient speed, and lack of coloration. The trade-off is a tiny sweet spot and a lack of absolute low-end frequencies.

My Upper East Side pal and Methodist vicar Steven Yagerman enjoys his original ESLs as the holy relics they are—they bring to life the voices of Ella, Frank, Nat, John, and Paul as I'd never heard them before. I also recall how, in 2015, Robin Wyatt of Robyatt Audiobrought a pair of beautifully restored ESLs into a small showroom as attendees jostled for a taste of their itsy-bitsy yet terrific sweet spot. Peter Walker had legendary history and, thus, experience with electrostatic technology; no doubt that wisdom has trickled down, to endure in Quad's upscale Z-series speakers and less expensive S models, the latter including the smaller S-1 stand-mount, the S-4 and S-5 floorstanders, and the S-C center channel.

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Design
The Quad S-2 is a two-way, ported design with a 5" mid/bass drive-unit featuring a Kevlar cone and manufactured in-house, and Quad's newly designed, 0.5" by 1.75" (12 by 45mm) True Ribbon tweeter. Its specifications include a frequency response of 48Hz–22kHz, ±3dB; a sensitivity of 87dB; impedance of 8 ohms; bass extension down to 37Hz, –6dB; and a crossover frequency of 3kHz. Each Quad S-2 measures 13" high by 7.1" wide by 10.25" deep and weighs 13.5 lbs.

"The ribbon tweeter in the S-2 is the same as in the S-1," said Jon Derda, of Quad's US distributor, MoFi Distribution, in an e-mail. "The Z-series tweeter is the same overall design, but has a larger surface area for an even smoother integration between the midbass and HF drivers."

The S-2's cabinet comprises varying layers of MDF, with internal "circumference" bracing. The cabinet is a beauty. Its rounded corners and rolled edges put me in mind of Eero Saarinen or Le Corbusier, architects whose structures combined subtle modernity with powerful lines drawn from nature. The Sapele Mahogany finish of my review samples was silken to the touch. (The S-2 is also available in Black Oak, Piano White, or Piano Black.) The S-2s come with a thin sheet of rubberized paper, from which can be peeled eight plastic nubs to be used as footers. Near the bottom of the rear panel are two pairs of handsome, matte-finish aluminum binding posts; near the top, a 11/4"-diameter port. Even the placements of these mechanical bits and bobs seem well thought out, for purposes functional and cosmetic.

In an effort to learn more about the S-2's design and construction, I contacted Peter Comeau, director of acoustic design for the Hi-Fi division of IAG Group; he replied by e-mail:

"The biggest problem with dome tweeters is that the diaphragm is rarely fully under the control of the motor system as the voice-coil is only attached at the circumference of the dome. What we often see is the center of the diaphragm moving in anti-phase to the voice-coil and, obviously, this results in a critical loss of transient information and therefore musical detail. With a ribbon tweeter the diaphragm IS the voice-coil, so to speak, and so is always under the control of the music signal from the amplifier. In that respect it is closer to the performance of an ESL and, thankfully for Quad, shares some of the same characteristics.

"The True Ribbon treble uses a thin, metal ribbon suspended in a strong magnetic field. The music signal is passed directly to the ribbon and causes a deflection due to the induced magnetism. As the ribbon is directly driven by the amplifier, its resolution of musical detail is very high. The S series ribbon is made from a lightweight metallic alloy which is stronger than pure aluminum. In addition the ribbon is given extra mechanical strength by a very light, and thin, deposition of polycarbonate—giving it a sandwich construction that allows higher power handling."

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Setup
The S-2s quickly found favor in my smaller rig, which occupies Listening Room A: 14' long by 8' wide by 14' high. I set up the Quads along one long wall on 24"-high steel stands, which put their tweeters at the height of my ears when I sit down to listen. Each speaker was 9" from the front wall (measured from the toed-in speaker's rear inside corner). A support wall in my apartment creates a barrier on the left that was 5" from one S-2's rear outside corner; the space to the right of the right speaker is relatively open. The speakers were 5' from my listening seat—I listened to them in the nearfield. This setup provided the most coherent, cohesive sound from LPs and CDs.

"Regarding setup," wrote Derda, "the ribbon tweeter has limited vertical dispersion, which reduces the effects of floor and ceiling reflections. It usually performs best aligning the tweeter at ear level of the listening position, or within a few degrees of ear level." I found this observation to be 100% spot on.

But in Listening Room B (12' L by 10' W by 12' H), placing the Quads 9" from the long front wall basically sapped their articulation. Repositioning them 27" out from the wall and 58" apart snapped their coherence into place.

Listening
In my smaller system in Room A, I listened to oud master Anouar Brahem's exotic Blue Maqams (CD, ECM 2580). The S-2's open, airy sound and smooth delineation of upper-frequency transients weren't the first things that impressed me. Instead, it was the speaker's fantastic reproduction of the lower midrange and bass—the lute-like oud, which looks like a pear sliced lengthwise in half, or a plump guitar with a split-back headstock, can go very low in pitch. Spinning the Christian McBride Big Band's Bringin' It (LP, Mack Avenue MAC1115) brought to the fore equally extraordinary lower-frequency tonnage allied with clarity. Both recordings presented nonfussy senses of immediacy and intimacy, as if the wall between me and the musicians—or, at least, between me and the mixing console—had been removed.

COMPANY INFO
Quad
US distributor: MoFi Distribution
1811 W. Bryn Mawr Avenue
Chicago, IL 60660
(312) 738-5025
ARTICLE CONTENTS

COMMENTS
Axiom05's picture

"Although the tweeter's output leads that of the woofer, their outputs meld relatively well, even if this graph does suggest that the optimal blend occurs just below the tweeter axis."

From the graph, how do you determine that the optimal blend is just below the tweeter axis? Thanks!

John Atkinson's picture
Axiom05 wrote:
From the graph, how do you determine that the optimal blend is just below the tweeter axis?

That very slight discontinuity in the step response just below the time axis at approximately 3.8ms suggests that the woofer's output needs to be moved forward in time a little. This could be achieved by moving the listener's ears down or the speakers up an inch or so.

John Atkinson
Editor, Stereophile

Axiom05's picture

I see that this same discontinuity is seen between the tweeter and the midrange of the B&W 800 Diamond and the 802 D3. This is consistent with the fact that the intended listening axis is just below the tweeter axis and why these speakers usually need a little forward tilt to sound best.

supamark's picture

those are some unusually dimensioned rooms... your building must be very very old.

ken mac's picture

No, really.

supamark's picture

Old houses/buildings always have weird dimensions. Everything is a "one-off" design. Hope (for your sake) it's rent controlled lol, that's become some mighty expensive real estate. Visited Manhatten before Guiliani was mayor, was a fun and interesting place (that sadly no longer exists).

Charles E Flynn's picture

From page 3 at http://www.quad-hifi.co.uk/upload/files/manual/20150817100845_23.pdf :

Quad crossover networks separate the treble and bass networks into two distinct sections, each connected by a dedicated pair of terminal posts. The enables the treble and bass components to be separately driven for optimum performance.

ken mac's picture

I would've loved to bi-wire these monitors for the review, but I have no bi-wire cables. Something to consider, for sure...

Charles E Flynn's picture

AudioQuest has an interesting set of recommendations regarding bi-wiring at http://www.audioquest.com/resource_tools/downloads/literature/learning_m... .

They make two potentially strategy-altering points that I have not seen widely discussed :

"Is BiWiring so important that you should spend twice as much on speaker cable?

BiWiring is actually a way to get higher performance for the same expenditure. The BiWiring question is not about how much money to spend, but how to maximize performance and value."

Later, the article has a diagram showing how a speaker that is capable of being bi-wired should be wired if it is not being bi-wired. The diagram is contrary to what many speaker makers show in their instructions. I asked a local dealer about this diagram, and he replied that "Everybody at the trade shows knows about this and wires their speakers that way." The relevant section is titled "Using Full Range Cables On BiWire Capable Speakers".

spacehound's picture

That well-known purveyor of snake oil sold via pseudo-scientific total gibberish, just wants to sell you twice as much of its overpriced lengths of wire.

"Full range cables"?

At the frequencies that even the best speakers are capable of even a straightened coathanger is "full range" and will supply far more current than any speaker will ever need.

DougM's picture

Seems to be an awesome little speaker for $999. I like the way many more manufacturers are using ribbon or AMT type tweeters these days. And, the IAG family of companies is really making some great affordable stuff, another example being the Diamond series from Wharfedale. I have the older Diamond 9.1s, and they sound great. And you gotta love a reviewer who uses Chet for some of his test discs. Great Taste!

ken mac's picture

I had the 10.2, absolutely wonderful speaker. Chet is the best!

Charles E Flynn's picture
ken mac's picture
mrkaic's picture

I have pair of slightly cheaper Quad S-1's and I drive them with a Quad VA-One. One gnarly combo, warmly recommended.

spacehound's picture

There are so many of these around at all sorts of prices that the speaker industry will soon be able to offer every hifi enthusiast in the world a different one.

Long-time listener's picture

"Both recordings presented nonfussy senses of immediacy and intimacy."

Senses? Excuse me, but hearing and sight would be two different *senses.* But since the immediacy and intimacy you speak of both came to you via your hearing, why not write, as everyone else does, "a wonderful sense of immediacy and intimacy." Forest here, not trees.

gbougard's picture

These speakers look yummy as hell, yet after reading your review, I don't know if those are for me
I produce Jamaican music with Sly & Robbie, one of the world's HEAVIEST rhythm sections, and love to listen to Reggae, Dancehall Hip Hop and Funk.
All these musics are bass and drum-heavy and the music you use to evaluate the speakers is not.
So do you think you could pop a record like DUBRISING by Sly & Robbie and crank it all the way to 11 and report back to me with your impression on how these speakers behaved when subjected to real drum and bass and heavy beats.
Thanks

iListen's picture

Which integrated would you pair with these?
Quads own? or the Sphinx?

toofastdad's picture

I just ordered a pair of Quad S2 speakers, do you think that pairing them with a NAD 3020 will have favourable results?

toofastdad's picture

Using the above combo Sly & Robbie sound amazing, the bass is very warm and rich — great speakers, I'm really pleased with my purchase. I just ordered a Musical Fidelity M2Si amp which I guess will make these babies sing. Joe Cocker's Sheffield Steel sounds really good (Sly & Robbie on drums and bass).

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